Officer Zhang did not enter this strange circle at first. Only Xiao and He entered the time cycle of the play. Zhang Cheng is the vice captain of criminal investigation in Jialin Public Security Bureau.

Zhang Cheng is a very capable and sober old criminal policeman with strong analytical and reasoning skills. He is the main person in charge of the explosion of bus No.45. Survivors Xiaohe were found in repeated cycles, and the cause of the explosion was found out bit by bit in their interrogation.

The ending at the beginning of "Officer Zhang"

Xiaohe, two people who didn't know each other originally, also had feelings in the cycle. Only by finding the source of the explosion and stopping it can they get out of this cycle. After repeated verification with Xiao, the murderer was finally locked into the driver Wang Xingde and the passenger Tao.

Officer Zhang is the police officer in charge of the minibus explosion. After listening to Li Shiqing's circular story, he didn't believe it at first, but with the communication, he gradually believed Li Shiqing's words. In a cycle, police officer Zhang died to protect the people in the car. Fortunately, in the last cycle, police officer Zhang came back to life.